#include<iostream>
using namespace std;
class Solution {
public:
    static int i;
    static int sum;
    Solution() {
        sum += i;
        i++;
    }
    int Sum_Solution(int n) {
        new Solution[n];
        cout << sum;
        return sum;
    }
};
int Solution::i = 0;
int Solution::sum = 0;
int main() {

    return 0;
}